/// <summary>
///
/// </summary>
/// <param name="inputStream"></param>
/// <param name="outputStream"></param>
/// <param name="mode"></param>
public void ProcessStream(Stream inputStream, Stream outputStream, StreamProcessMode mode)
{
// 当输入流不可读时应该抛出异常终止程序。
if (!inputStream.CanRead)
{
throw new NotSupportedException("Input stream not support reading");
}
// 当输出流不可写时应该抛出异常终止程序。
if (!outputStream.CanWrite)
{
throw new NotSupportedException("Output stream not support writting");
}
long outputStreamCurrentPosition = 0;
if (outputStream.CanSeek)
{
outputStreamCurrentPosition = outputStream.Position;
}
// 将上一个输出流（上一个SOAP扩展的输出流就是当前SOAP扩展的输入流）复位再后读取经过上一个SOAP扩展解析的数据流。
if (inputStream.CanSeek)
{
inputStream.Position = 0;
}
byte[] buffer = new byte[BufferSize];
try
{
ProcessModeStream(inputStream, outputStream, mode, buffer);
}
catch (Exception ex)
{
throw new ApplicationException("数据处理错误 : " + ex.Message, ex);
}
finally
{
// 在整个数据流链表中，必需手动关闭输入流，但不能关闭输出流。
inputStream.Close();
/* 当优先级最低的SOAP扩展（即最后一个过滤处理器）在处理完从网络中接收过来的数据时，
* 必需将输出流复位到经当前SOAP扩展处理后前的位置上，否则系统从这个流中读取数据时
* 必定遇到EOF异常。
* */
if (outputStream.CanSeek)
{
outputStream.Position = outputStreamCurrentPosition;
}
}
}
/// <summary> /// /// </summary> /// <param name="inputStream"></param> /// <param name="outputStream"></param> /// <param name="mode"></param> protected abstract void ProcessModeStream(Stream inputStream, Stream outputStream, StreamProcessMode mode, byte[] buffer);
/// <summary>
/// 集中处理所有数据流的压缩或者解压缩，具体的压缩和解压功能
/// 在具体的子类中通过重写CompressStream和DecompressStream
/// 方法来实现。
/// </summary>
/// <param name="inputStream"></param>
/// <param name="outputStream"></param>
/// <param name="mode"></param>
/// <param name="buffer"></param>
protected override void ProcessModeStream(Stream inputStream, Stream outputStream, StreamProcessMode mode, byte[] buffer)
{
if (mode == StreamProcessMode.Compress)
{
CompressStream(inputStream, outputStream, buffer);
}
else if (mode == StreamProcessMode.Decompress)
{
DecompressStream(inputStream, outputStream, buffer);
}
else
{
throw new NotSupportedException("Not support compression mode");
}
}
